-encoding and -source in module-info.java

[Peter Jensen]

On 01/25/12 12:47, Jesse Glick wrote:
> On 01/25/2012 02:16 PM, Alex Buckley wrote:
>> All those things are implementation details and so don't belong in a 
>> module declaration as defined by the JLS.
>
> Then the encoding needs to be specified somehow in the source root 
> outside of a module declaration (such as my proposed $root/encoding 
> file). I do not really care whether the JLS ever mentions it or not, 
> so long as javac interprets disk files with a predictable encoding - 
> so that all Java language tools which operate on files (*) will be 
> able to parse a given module source tree the same way. Currently they 
> need out of band information to do so, and that is a significant problem.
A Java compiler may support different encodings, it may support 
compilation of source code written against different version of the JLS, 
it may support generation of Java byte code relying on APIs as defined 
by different versions of the JLS, ...

Specifying such options, in whatever format, means specifying common 
capabilities where it has previously been open to the implementation.

While there might be sense in doing so, I fail to recognize why modules 
make this any more, or less, of an issue. Did I miss an argument why 
this is especially critical for modules? Or is it more a matter of 
filling an existing void?